Dobby.



B.. F. WATGHORN.

DOBBY.

APPLIouIoN FILED D20. s, 1912.

1,074,670. Patented oeuf/,1913.

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l BOBBY.

APPLICATION FILED DEO. 5, 1912.

Patented 0G13. 7, 1913.

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R F. WATGHORN.

DOBBY.

APPLIGATION FILED 1130.5., 1912.

Patented 00L?, 1913.

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ROBERT F. WTCHORN, OF MILLBURY, MIASSACHUSETTS.

DOBBY.

T 0 all whom t may concern Be it known that T, RoBERT F. WATCH- oRN, acitizen of the United States, residing at Millbury, in the county ofWorcester and State of Massachusetts, have invented anew and usefulDobby, of which the following is a specification.

This invention relates to a dobby capable of general application, and inwhich the harness jacks are moved positively in one direction only, thereturn movement of the harnesses being accomplished by means of springconnections.

A dobby constructed in accordance with my invention comprises importantadvantages when used upon any form of work ordinarily produced by a.dobby loom,A but is particularly adapted tothe production of that classof fancy goods which are termed full-turn lenos. The production of thistype of fancy weave upon a dobby of ordinary form, such for instance asthat shown in the patent to Crompton, No. 771,462, of Oct. 4, 1904,involves a rearrangement of parts and an addition of auxiliarymechanism. Leno weaving of this description is usually four harnesswork, the harnesses taken in order from front to back being designatedas the doup harness, the front standard harness, the crossover harness,and the back standard harness. The operation of the first and lastmentioned of these harnesses presents no difficulties, as the harnesseshave the usual full-up or full-down motion, and the order in which thesemotions take place may be readily controlled by the usual pattern chain.The so-called front-standard and cross-over harnesses however, have apeculiar motion for the production of which the ordinary dobby is notwell adapted. The front-standard harness is maintained in the upper shedat each pick, but must be brought to half-way down or to middle positionbetween each two successive picks. To accomplish this on the ordinarydobby, it is necessary to use two jacks for each harness, and to inserttemporary attaching means between the second or auxiliary jack and theharness. With this arrangement, one jack allows the-harness to descendunder the influence of the usual retracting spring, until it reachesmid-position when the second jack traveling in the opposite directionpicks up the harness and raises it again to the upper shed.

Speccation of Letters Patent.

Application filed December 5, 1912.

Patented Oct. 7, 1913.

Serial No. 735,018.

The connections necessary to permit two jacks to operate upon a singleharness are of more or less delicate construction, and much diiiicultyis experienced in their operation. The movement of the cross-overharness presents still more serious difficulties. This harness isnormally maintained in the lower shed at each pick, but must be raisedto mid-position between each two successive picks. This movement cannotbe performed by the ordinary harness jacks, as there is no method bywhich a jack .when once started in the upward direction can be stoppeduntil it has performed its full stroke. TvVith the usual dobby,therefore, it is necessary to disconnect the cross-over harness entirelyfrom the usual jack operating mechanism and to provide some form ofindependent auxiliary mechanism commonly known as a jumper to operatethe cross-over harness.

It is one of the objects of my invention to produce a dobby1 in whichthe peculiar motions of the front standard and crossover harnesses maybe secured merely by the proper pinning of the pattern chain, andwithout the use of auxiliary mechanism or rearrangementof parts.

Another object of my invention is to provide improved means foroperating the pattern chain and hook-lifting mechanism.

Further objects of my invention will ap pear in the followingspecification.

Reference is tobe had to the accompanying drawings in which- Figure l isan end elevation of a leno dobby constructed in accordance with thisinvention; Fig. 2 is a front elevationthereof, and Fig. 3 is a verticalsectional view on the line 3 3 of Fig. l.

The invention is shown as applied to a dobby provided with jacks 4. Thejacks are pivoted on a transverse rod 5 and removably supported thereon.Each one is pro-vided with a curved slot 6 through which slots passes arod 7 supported in stationary position on the frame to limit theirmotion for the purpose of lifting the harnesses in the usual way. Themeans for operating the jacks will now be described.

With each jack is pivotally connected a hook 9 and to it is pivoted asecond hook 10. Thus these hooks reciprocate in pairs. The mechanismillustrated herein is intended to be run by a crank or eccentric on thecrank-shaft (not shown) of the loom.

This crank is Connected with a link 11 which is adjustably connectedwith an arm 12 having a slot therein for the connection. This arm isfixed on a rock shaft 13 supported by the frame and is thus given acomplete up and down reciprocation for each revolution of the crankshaft, and hence for each pick of the shuttle. On the shaft 18 are apair of arms 14 extending in opposite directions and connected withlinks 15 and 16, respectively, which are in turn connected withreciprocating knives 17 and 18. Thus the two knives reciprocatealternately and each performs a complete reciprocation/f for each pickof the shuttle. The knife 17 operates under the set of hooks 9 and theknife 18 operates under the hooks 10. The links 16, as shown in F ig. 2,are pivoted to the arms 14 at a greater distance from the axis than thelinks 15, and hence the knife 18 receives a greater travel than theknife 17. Each knife has also a certain amount of idle travel or lostmotion at the left extreme of its travel, as shown at 18 in Fig. 2, andat 17 Yin Fig. 3, this idle travel being beyond the limit of travel ofthe hooks 9 and 10 toward the left. The arms 14 are so proportioned thatthe effective travel of the knife 17 is substantially one half that ofthe knife 18. 1n other words, the knife 17 which engages all of the jackhooks 9 at each pick raises them only half way, thus bringing the warpthreads controlled thereby to substantially horizontal position, whilethe knife 18 which engages certain of the hooks 10 as determined by thepattern chain moves those hooks to the extreme righthand position inFig. 2, thus raising the Warp threads cont-rolled thereby to the extremeupward position. This arrangement possesses certain peculiar advantagesin the production of lenos which will be hereinafter explained, but italso possesses distinct advantages when applied to any weave in whichone or more of the harnesses remains in the lower shed for a successionof two or more picks. On the rock shaft 18 is another arm 2O with whichis connected a link 21 operating to oscillate an arm 22 on a short shaft28 which is provided with a spring-pressed roll 24 adapted to cooperatewith a cam wheel 25 on the chain cylinder shaft 26. This shaft issupported on another arm 27 extending from the shaft 28 and theoscillation of the arm 20 causes the chain cylinder 28 to rise and fallat regular intervals. At each reciprocation of the cylinder and whilethe pins are substantially out of contact with the tumblers, thecylinder is turned one step by any suitable means, such as a ratchet 25,(see Fig. 2) coperating with a hooked pawl mounted upon a stud fixed tothe frame of the dobby. The pattern cylinder is thus advanced one stepfor each vertical reciprocation thereof or hooks 10. lVhen the cylinderrises the wires 32 corresponding to the pins then at the top ofthecylinder drop and thus allow the hooks 10 to drop.

This construction is designed to overcome certain objections to the useof the rigidly mounted attern cylinder heretofore coinmon and cisclosedin the patent to Crompton mentioned, in which the pins have a slidingmotion relative to the tumblers. Vhen metal pins are used this constantsliding motion results in excessive wear of the tumblers, and when it issought to avoid this wear by the use of wooden pins, the 'pinsfrequently break and cause imperfections in the cloth which continueuntil the broken pin is detected. In my arrangement the pattern cylinderis turned when the pins are substantially out of contact with thetumblers, and are then moved toward the tumblers in a direct linealmotion so v'that theV wear due to the sliding contact is eliminated.A

The operation of my device in the roduction of full-turn lenos will nowbe explained For the operation of the front standard harness which, asbefore stated, is normally in the upper shed and is brought half downand returned to upper positionV between each two successive picks, it ismerely necessary to arrange the pattern chain so that the hook 10connected with said harness shall remain substantially in lowered oroperative posi-V tion. Assuming that the harness is up and the knife 18is about-'to commence its travel toward the left in Fig. 3, it will beseen that the harness will be lowered until the hook 9 contacts with theknife 17, which is at this time moving toward the right in Fig.

8 and which will prevent the retracting Y springs from depressingtherharness below the horizontal position of the warp threads controlledthereby. As the knife 18 performs a complete reciprocation and returnsto the extreme right position between each two successivev picks, itwill be evident that if the hook 10 is allowed to remain in loweredposition, the knife 18 will again assume control of said hook upon itsreturn travel toward the right and will return the harness to extremeupper position.v

The operation of the so-called cross-over harness which is normally inthe lower shed and is raised to mid-position between each two picks isaccomplished by simply maintaining the hook 10 connected therewith inraised position, so that the harness is operated entirely by the knife17 through the hook 9. This knife, as before stated, raises all of theharnesses to mid-position between each two picks of the loom, andtherefore, communicates precisely the desired motion to the cross-overharness. It will be evident that the raising of all of the harnesses tomid-position will relieve the warp threads inv the lower shed of theexcessive strain in beating up, which is experienced when certain of theharnesses are maintained in lowered position during the forward beat ofthe lay.

Although I have illustrated and described one form in which theinvention may be made, I am aware of the fact that modications can bemade therein without departing from the scope of the invention asexpressed in the claims. Therefore, I do not wish to be limited to thedetails of construction herein shown and described, but

I/Vhat I do claim is Y 1. A dobby comprising a set of jacks, a pair ofhooks connected to each jack, and a reciprocatingknife for moving eachhook, each of said knives making a complete reciprocation during eachpick of the loom, and one of said knives having an eective travelsubstantially twice that of the other knife.

2. A dobby comprising a set of jacks, means to move all of sai-d jacksto mid-positio-n at each beat of the lay, and selective means to movecertain of said jacks to extreme upper position.

3. A loom having in combination harnesses, jacks connected to saidharnesses, hooks mounted on said jacks, and a second set of hookspivotally mounted on said first mentioned hooks, means for moving saidrst mentioned hooks to raise all of the harnesses to mid-position ateach beat of the lay, means for moving the harnesses connected tocertain of said second mentioned hooks to eXtreme upper position, andpat tern means for selecting said last mentioned harnesses.

4. In a dobby, a jack, a pair of hooks connected to said jack, and meansoperable upon said hooks to raise said jack to eXtreme upper positionfor successive picks and to permit said jack to be moved to mid-positionbetween such successive picks.

5. In a dobby, a jack, a pair of hooks connected to said jack, and meansoperable upon said hooks to raise said ]ack from eX- treme lower tomid-position and to permit said jack to return to eXtreme lower positionbetween two successive picks of the loom.

6. In a dobby, a pair vof reciprocating knives, a pattern cylinder, anoscillating shaft, means on said shaft to reciprocate said knivessimultaneously in opposite directions, additional means on said shaft toraise and lower said cylinder, an operating arm on said shaft, and alink directly connecting the arm to the crank shaft of `theloom,.whereby the knives and cylinder each perform a complete cycle ofmovements at each revolution of the crank shaft.

7 In a dobby, a pattern cylinder, pattern pins mounted thereon, a set oftumblers,

and means for both raising and lowering said cylinder between each twosuccessive picks of the loom, said cylinder being rotated step by stepwhen said pins are substantially out of contact with sai-d tumblers.

8. In a dobby for looms, the combination with a set of jacks, of hooksconnected with the jacks, additional hooks connected with the firstnamed hooks and movable therewith, two knives, one adapted to coperatewith each vset of hooks, and means for simultaneously reciprocating saidknives in opposite directions and for returning them to their originalpo-sitions during each complete beat of the lay.

9. In a loom, a crank shaft in combination with a set of jacks, hooksconnected with the jacks, additional hooks connected with the firstnamed hooks and movable therewith, two knives, one adapted to coperatewith each set of hooks, an oscillating shaft having arms projectingtherefrom in opposite directions, a link from each arm to one of saidknives for operating it, and an additional arm on sai-d oscillatingshaft connected by a link to the crank shaft, whereby each knife isgiven a complete reciprocation for each beat of the lay.

In testimony whereof I have hereunto set my hand, in the presence of twosubscribing witnesses.

ROBERT F. WATCHORN. IVitnesses:

Rosa WATCHORN, C. FoRRnsT Wasson.

Copies of this patent may be obtained for ve cents each, by addressingthe Commissioner of Patents, Washington, D. C.

